Selective ring opening of decalin with Pt–Ir/Al2O3 catalyst prepared by catalytic reduction

Abstract

The reaction of selective ring opening using alumina supported Pt–Ir catalysts with and without Mg addition was studied. The catalysts were prepared by the method of catalytic reduction, having 1 wt% of Pt whereas the Ir content varied in the range 0.1–0.6 wt%. Electron diffraction showed that the method of preparation leads to catalysts with strong interaction between Pt and Ir being observed the presence of a solid phase of Pt–Ir. In the catalysts without Mg no changes in the hydrogenolysis activity was observed as the Ir content increases. However, a decrease both in acidity and dehydrogenating activity was observed. In the Mg containing catalysts, the addition of Ir increases the acidity, the dehydrogenating and hydrogenolytic activity. For the isomerization reaction of npentane it was found that the addition of Ir improves the stability of the catalysts and formation of isomers of C5 in both series of catalysts (with and without Mg). The conversion of decalin by ring opening depends on the content of Ir for both studied series.